This invention claims the benefit of Japanese patent applications No. 2000-370527, filed on Dec. 5, 2000, and No. 2000-375378, filed on Dec. 11, 2000, which are hereby incorporated by reference.
1. Field of the Invention
The present invention relates to a vehicle light for use as an automobile headlight or a supplementary headlight such as a fog light etc., and more particularly relates to a vehicle light which is designed for providing a low-beam mode light distribution pattern, capable of selectively providing a portion of light rays into a travelling direction of the vehicle such that a light amount in the travelling direction can be increased for providing a driver of the vehicle with improved visibility into the travelling direction of the vehicle. For example, when the vehicle drives on a curve to the left, a light amount to the left front of the vehicle can be increased. When the vehicle drives on a straight road at a relatively high speed, a light amount to a far front central area of the vehicle can be increased.
2. Description of the Related Art
Generally, a projection-type vehicle light comprises a light source, a major reflecting surface such as an ellipse group reflecting surface for reflecting light rays emitted from the light source in a direction generally forward, a projection lens of a convex lens whose convex surface is aspherical, etc., and a shade located in the vicinity of a focus of the projection lens. Light rays reflected by the major reflecting surface and directly come from the light source converge in the vicinity of the focus of the projection lens to provide a focused image of light. The projection lens projects the focused image of light upside down with its left side to be the right side into a forward direction while enlarging the focused image, thereby the projection-type vehicle light illuminates a predetermined area on a road. The shutter cuts off an unnecessary portion of light for formation of light distribution pattern(s) of the vehicle light. The unnecessary portion of light is typically a portion which generally illuminates in an upper right forward direction of the vehicle after being projected by the projection lens, which can be glare light to a driver of a car driving on an on-coming lane. Since light rays illuminating in the upper right forward direction of the vehicle are prohibited, an illuminated area of the vehicle light has a relatively short distance to the front of the vehicle at the side of the on-coming lane.
FIG. 25(A) illustrates a prohibited portion A of a low beam mode light distribution pattern on a screen defined by regulations and an actual light distribution pattern B on the screen for a vehicle driving on a left lane. The prohibited portion A is an area shown by slanting lines which light rays are not allowed to enter into in the low beam mode of the light distribution pattern. A horizontal line of the prohibited portion A located on the right side of the vertical axis is consistent with a horizontal axis on the screen. An inclined line of the prohibited portion A located on the left side of the vertical axis extends from a crossed point of a vertical axis and the horizontal axis on the screen to the left upward at 15 degrees relative to the horizontal axis. The actual light distribution pattern B is located not to enter into the prohibited portion A at any time of operation of the vehicle light.
When the vehicle drives on a curve, it is preferable for the vehicle light to provide an increased amount of light into a traveling direction, i.e., forward of the curve, of the vehicle in comparison with when driving on a straight road for obtaining superior long distance visibility on the curve. More specifically, when the vehicle drives on a curve to the left, it is preferable to increase an amount of light rays which illuminate a left side in front of the vehicle. On the other hand, when the vehicle drives on a curve to the right, it is preferable to increase an amount of light rays which illuminate a right side in front of the vehicle.
However, when the vehicle travels on a curve to the right, or turn around a corner to the right, even though the driver would like to see more clearly the forward of the curve or corner, there is a potential that sufficient bright field of vision is not obtained. The forward of the curve or corner is on the side of the on-coming lane. Since a cut-off line of the low beam mode light distribution pattern is fixed, the illuminated distance to the front right side from the vehicle cannot be increased.
Further, when the vehicle travels at a relatively high speed, a distance between the vehicle and another car traveling ahead increases. In this case, since light distribution characteristics of the vehicle light are fixed, an illuminated distance to the front of the vehicle results in being relatively decreased. It may happen that sufficient long distance visibility can not be obtained when the vehicle travels at a relatively high speed.
In order to achieve superior long distance visibility on the curve, in a conventional vehicle light, a reflecting surface laterally moves depending on steering angle while a location of a light source is fixed. The conventional projection-type vehicle light has the following problems.
In order to achieve sufficient change of a light distribution pattern between before and after the reflector is moved in accordance with the change of steering angle, a large space is required in a housing for moving an optical axis of the reflector at a large angle. Therefore, an entire size of the conventional vehicle light must be enlarged, and designing of the vehicle light tends to be difficult. Further, there exists gaps between a periphery of the reflector and aperture edge of the housing for allowing movement of the entire reflector, which deteriorates aesthetic appearance of the conventional vehicle light. Furthermore, a transparent front lens cannot be used, because it is difficult to obtain sufficient change of light distribution from when driving on a straight road to when driving on a curve solely by movement of the reflector. Prismatic cuts on an inner surface of the front lens are required to obtain the sufficient change of light distribution with superior visibility when a direction of an optical axis of the reflector is changed.
In another conventional vehicle light for the cases both when the vehicle drives on a curve or travels at a relatively high speed, an optical axis of the vehicle light is changed from a horizontal direction to an upward direction by moving an entire set of the vehicle light. In a still another conventional vehicle light, a shutter is moved to the downward. However, these two methods bring about increase of light amount illuminated to a still another vehicle running ahead of the vehicle. This problem is significant for a still another vehicle ahead of the vehicle running on a travelling lane when the vehicle travels on an over-passing lane. In general, a height of location of an automobile headlight disposed in an automobile body is lower than a position of a side mirror disposed in the automobile body. Therefore, if an illuminated light amount to the upward from the vehicle is increased, the upwardly illuminated light is reflected by the side mirror of another vehicle running ahead of the vehicle, which may cause to glare the driver in the vehicle running ahead of the vehicle on the traveling lane.
As a preventive means from the glare light, it is possible to detect a car running ahead of the vehicle, and to prevent from increasing light amount to the upward depending on detection results, e.g., a car running ahead of the vehicle is detected. However, a device for performing the detection and the illumination direction change must be large and expensive. Further, it is rarely that there is no car running ahead of the vehicle. Accordingly, this method is not very effective.
Then, the invention is, in part, intended to provide a vehicle light that includes a front lens substantially free from prismatic cuts, capable of easily changing an optical axis of a reflector, i.e., a general direction of a predetermined amount of light rays incident on the reflector, at a large angle by a simple structure while providing superior light distributions for both driving on a curve and driving on a straight road at a high speed. Specifically, when the vehicle drives on a curve or turn around a corner, the vehicle light is capable of increasing an illuminated distance to the front of the vehicle at the side of an on-coming lane without providing glare light to a driver of a car running on an on-coming lane.
In order to resolve the aforementioned problems in the related art, the present invention provides vehicle lights designed to alleviate these problems and to provide improved efficiency, decreased cost of manufacture, and improved aesthetic characteristics. Examples of preferred embodiments of the invention are described as follows. In a first aspect of the invention, a vehicle light includes a light source, a major reflecting surface reflecting light rays from the light source into a forward direction, a projection lens through which light rays from the light source and from the major reflecting surface pass in a converging manner to be directed to a predetermined direction, a shutter located in a light passageway from the light source to the projection lens for cutting-off an unnecessary portion of image of light in the vicinity of a focus of the projection lens on formation of a light distribution pattern, wherein the vehicle light comprises following five reflecting surfaces in addition to the major reflecting surface. A first reflecting surface located at a predetermined side of the major reflecting surface, e.g., when the vehicle light is designed to be disposed on a left front corner of the vehicle body, the predetermined side of the major reflecting surface means a right side of the major reflecting surface. The first reflecting surface reflects light emitted from the light source into a forward direction of the vehicle light. A second reflecting surface of an ellipse group reflecting surface such as a rotated elliptic surface having a first focus located substantially on the light source and having a second focus at a predetermined position. A longitudinal axis of the second reflecting surface is across an optical axis X of the vehicle light which passes through the light source. The second reflecting surface can be rotated around its longitudinal axis, thereby the second reflecting surface can be inserted in or removed from an optical path of light traveling from the light source to the first reflecting surface. When the second reflecting surface is removed from the optical path, the second reflecting surface is located in a shadow region of a third reflecting surface. The third reflecting surface is an ellipse group reflecting surface such as a rotated elliptic surface having a first focus in the vicinity of the light source and a longitudinal axis which is across the optical axis X of the vehicle light. A fourth reflecting surface has a focus substantially on the second focus of the second reflecting surface, and directs light rays from the second focus into a front outer side direction of the vehicle, which is inclined to a predetermined side of the vehicle light, e.g., when the vehicle light is designed to be disposed on the left front corner of the vehicle body, the predetermined side of the vehicle light means a left side of the vehicle light. A fifth reflecting surface has a focus in the vicinity of the second focus of the third reflecting surface, and directs light rays from third reflecting surface into a forward direction, which is also a rather downward direction, of the vehicle light. The direction of such light reflected by the fifth reflecting surface is laterally wide in a horizontal cross-sectional view of the vehicle light.
The first reflecting surface can be preferably a parabolic group reflecting surface such as a parabolic free-curved surface having a focus in the vicinity of the light source.
In a second aspect of the invention, a vehicle light can include a light source, a major reflecting surface reflecting light from the light source into a forward direction, a projection lens through which light rays from the light source and from the major reflecting surface pass in a converging manner to be directed to a predetermined direction, and a shutter located in an optical path of light from the light source to the projection lens for cutting-off an unnecessary portion of image of light in the vicinity of a focus of a projection lens on formation of a light distribution pattern, further comprising following six reflecting surfaces in addition to the major reflecting surface. A first reflecting surface located at a predetermined side of the major reflecting surface, e.g., when the vehicle light is designed to be disposed on a left front corner of the vehicle body, the predetermined side of the major reflecting surface means a right side of the major reflecting surface. The first reflecting surface is an ellipse group reflecting surface such as a rotated elliptic surface having a first focus in the vicinity of the light source and a second focus at a predetermined position. The first reflecting surface reflects light emitted from the light source in a converging manner to its second focus. A second reflecting surface is an ellipse group reflecting surface such as a rotated elliptic surface having a longitudinal axis which is across the optical axis X of the vehicle light. A first focus of the second reflecting surface is located in the vicinity of the light source. The second reflecting surface can be rotated around its longitudinal axis allowing to be inserted in or removed from an optical path of light from the light source to the first reflecting surface. When the second reflecting surface is removed from the optical path, the second reflecting surface is located in a shadow region of a third reflecting surface. The third reflecting surface is an ellipse group reflecting surface such as a rotated elliptic surface having its longitudinal axis which is across the optical axis X of the vehicle light. A first focus of the third reflecting surface is located in the vicinity of the light source. A fourth reflecting surface has a focus in the vicinity of the second focus of the second reflecting surface, and directs light rays from the second focus into a front outer side direction of the vehicle, which is inclined to a predetermined side of the vehicle light, e.g., when the vehicle light is designed to be disposed on the left front corner of the vehicle body, the predetermined side of the vehicle light means a left side of the vehicle light. A fifth reflecting surface has a focus in the vicinity of the second focus of the third reflecting surface, and directs light rays from third reflecting surface into a forward direction, which is also rather downward direction, of the vehicle light in a vertical cross sectional view, and a laterally wide direction relative to the optical axis X of the vehicle light in a horizontal cross sectional view. A sixth reflecting surface has a focus in the vicinity of the second focus of the first reflecting surface, and reflects light from the first reflecting surface to a forward direction of the vehicle light.
In a third aspect of the invention, a vehicle light can include a light source, a major reflecting surface for directing light emitted from the light source to a forward direction, a projection lens through which light rays from the light source and from the major reflecting surface pass in a converging manner to be directed to a predetermined direction, and a shutter located in an optical path from the light source to the projection lens for cutting off an unnecessary portion of image of light rays in the vicinity of the focus of the projection lens on formation of a light distribution pattern, and following five reflecting surfaces. A first reflecting surface is an ellipse group reflecting surface having a first focus in the vicinity of the light source. The first reflecting surface is located at a predetermined side of the major reflecting surface, e.g., when the vehicle light is designed to be disposed on a left front corner of the vehicle body, the predetermined side of the major reflecting surface means a right side of the major reflecting surface. The first reflecting surface reflects light emitted from the light source to the forward, preferably in the vicinity of the focus of the projection lens. A second reflecting surface is an ellipse group reflecting surface such as a rotated elliptic surface having a first focus in the vicinity of the light source. A longitudinal axis of the second reflecting surface is across the optical axis X of the vehicle light. The second reflecting surface can be rotated around its longitudinal axis such that the second reflecting surface can be inserted in and removed from an optical path from the light source to the first reflecting surface. When the second reflecting surface is removed from the optical path, the second reflecting surface is located in a shadow region of a third reflecting surface. The third reflecting surface is a rotated elliptic surface having a first focus in the vicinity of the light source and a second focus at a predetermined position, and reflects light rays from the light source to a fifth reflecting surface. A fourth reflecting surface has a focus in the vicinity of the second focus of the second reflecting surface, and directs light from the second reflecting surface to a front outer side direction of the vehicle, which is inclined to a predetermined side of the vehicle light, e.g., when the vehicle light is designed to be disposed on the left front corner of the vehicle body, the predetermined side of the vehicle light means a left side of the vehicle light. A fifth reflector has a focus in the vicinity of the second focus of the third reflecting surface, and reflects light from the third reflecting surface to a forward direction of the vehicle light, which is also rather downward direction, in a vertical cross-sectional view. The fifth reflector reflects light rays into a laterally wide direction relative to the optical axis X of the vehicle light in a horizontal cross-sectional view. Light rays reflected by the first reflecting surface are incident to the projection lens. When light rays pass through the projection lens, the light rays are refracted in a converging manner by a predetermined degree to the forward of the vehicle light.
In the vehicle lights according to the first to third aspects of the present invention, light rays which are reflected by the first reflecting surface are incident to the projection lens, such light rays travel to a forward direction while being converged by a predetermined degree by the projection lens when passing through the projection lens. Light rays emitted from the light source to the third reflecting surface are reflected by the third reflecting surface and further by the fifth reflecting surface. The fifth reflecting surface reflects such light rays into a laterally wide direction in a horizontal cross sectional view, and into a front direction which is also a rather downward direction in a vertical cross-sectional view of the vehicle light.
In the above described structures, when the second reflecting surface is located in the optical path from the light source to the first reflecting surface, light rays traveling from the light source to the first reflecting surface are not incident to the first reflecting surface, and are reflected by the second reflecting surface, and further by the fourth reflecting surface, and then travel into a forward direction of the vehicle light, which is inclined to the predetermined side of the vehicle light, and illuminates a road side such as a curb. Accordingly, when traveling on a curve to the left or right, or turning around a corner, the vehicle lights of the present invention can brightly illuminate a traveling direction of the vehicle along the curve or the corner.
On the other hand, when the second reflecting surface is located away from the optical path from the light source to the first reflecting surface, light rays traveling from the light source to the first reflecting surface are incident on the first reflecting surface, and reflected by the first reflecting surface to a forward direction of the vehicle, thereby the vehicle light can illuminate an area in the vicinity of a center line on the road when the vehicle is travelling on a straight road.
By movement of the second reflecting surface, an illumination direction of light incident on a predetermined portion of the reflector can be selectively switched between a first light distribution to the center forward direction of the vehicle light by the first reflecting surface and a second light distribution to the front side direction which is inclined to the predetermined side of either left or right by the fourth reflecting surface. In the vehicle lights according to the first to third aspects of the present invention, it is sufficient to move only the second reflecting surface in order to change an illuminated area on the road, i.e., light distribution characteristics of the vehicle light. Accordingly, a relatively small space for the movement of the second reflecting surface is required for change of the light distribution characteristics of the vehicle light. When the second reflecting surface is removed from the optical path from the light source to the first reflecting surface, the second reflecting surface does not prohibit light rays from traveling from the light source to the first reflecting surface, because the second reflecting surface is located in a shadow region of the third reflecting surface, i.e., at a backside of the third reflecting surface when viewed from the light source position.
By the movement of the second reflecting surface, an illuminated area on the road, in other words, a general traveling direction of a portion of luminous flux incident to a predetermined portion of the reflector can be switched by a relatively large angle relative to the light source position in a horizontal view. Further, light distribution characteristics, such as light intensity or entire shape, of the variable light distribution element can be flexibly designed by adjusting designing parameters of the second and fourth reflecting surfaces. Therefore, even in case that a transparent front lens which is substantially free from prismatic cuts is adopted in the vehicle light, the vehicle light can provide sufficient visibility to a front side area in a travelling direction of the vehicle when the vehicle travels on a curve, e.g. when the vehicle travels on a curve to the left, the visibility in the front left area of the vehicle is improved.
In the first through third aspects of the present invention, a movable part for switching the illuminated area on the road is only the second reflecting surface having a relatively small entire size. Accordingly, a mechanism for driving the second reflecting surface can be small with a simple structure. Therefore, it is easy to design the mechanism. Further, there exists a small gap around the second reflecting surface for movement of the second reflecting surface. However, the gap never be significantly large to an extent that the gap is noticeable and deteriorates aesthetic appearance of the vehicle light.
If the first reflecting surface is a parabolic group reflecting surface having a focus in the vicinity of the light source, light rays reflected by the first reflecting surface can be substantially parallel light, and travel forward of the vehicle to illuminate a predetermined area in the vicinity of a center line on the road when the vehicle travels straight ahead.
In the vehicle light described above, light rays, which directly come from the light source or are reflected by the major reflecting surface, are preferably incident to the projection lens. The projection lens refracts such light rays in a converging manner by a predetermined degree to the forward of the vehicle light. Light rays reflected by the third reflecting surface can be further reflected by the fifth reflecting surface. The fifth reflecting surface reflects such light rays to the forward of the vehicle with a large width in a horizontal cross-sectional view, and to a rather downward direction in a vertical cross-sectional view.
When the second reflecting surface is inserted in the light passageway from the light source to the first reflecting surface, light rays emitted from the light source to the first reflecting surface do not become incident on the first reflecting surface, but are reflected by the second reflecting surface, then by the fourth reflecting surface. The fourth reflecting surface reflects light rays into a forward direction of the vehicle light, which can be inclined to a predetermined side, either left or right, of the vehicle, and can illuminate a roadside such as a curb or a shoulder. If the fourth reflecting surface is located on the left side of the major reflecting surface while the first reflecting surface is located on the right side of the major reflecting surface, the light reflected by the fourth reflecting surface travel into the left front direction of the vehicle light. If the fourth reflecting surface is located on the right side of the major reflecting surface while the first reflecting surface is located on the left side of the major reflecting surface, the light reflected by the fourth reflecting surface travel into the right front direction of the vehicle light. Accordingly, when the vehicle drives on a curve or corner to the left, the vehicle light located on the left side of the vehicle body can illuminate forward of the curve, i.e., a left side front of the vehicle, with an increased illuminated area, while the vehicle light located on the right side of the vehicle body can illuminate the road intensively to the center front.
When the second reflecting surface is located away from the light passageway from the light source to the first reflecting surface, light rays emitted from the light source toward the first reflecting surface are incident on the first reflecting surface. The first reflecting surface can reflect such light rays to the sixth reflecting surface. The sixth reflecting surface reflects such light rays to a forward direction of the vehicle light, and an area in the vicinity of the center line on the road is thus illuminated.
As described in the above, a portion of a light distribution pattern of the vehicle light can be selectively switched by movement of the second reflecting surface between a first light distribution pattern for illuminating forward of the vehicle by the first and sixth reflecting surfaces and a second light distribution pattern for illuminating a front direction of the vehicle, which is inclined to a predetermined side, i.e., either left or right, of the vehicle light. If the fourth reflecting surface is located on the left side of the major reflecting surface while the first and sixth reflecting surfaces are located at the right side of the optical axis of the vehicle light, the light reflected by the fourth reflecting surface travels to the left front of the vehicle. If the fourth reflecting surface is located on the right side of the major reflecting surface while the first and sixth reflecting surfaces are located at the left side of the optical axis of the vehicle light, the light reflected by the fourth reflecting surface travels to the right front of the vehicle. In the structure described in the above, it is sufficient to move only the second reflecting surface in order to change an illuminated area, i.e., light distribution characteristics, of the vehicle light. In order to change the location of the second reflecting surface, a relatively small space is sufficient for the movement of the second reflecting surface. Further, when the second reflecting surface is removed from the light passageway from the light source to the first reflecting surface, the second reflecting surface can be located in a shadow region of the third reflecting surface, i.e., a back surface of the third reflecting surface in a viewpoint from the light source. Accordingly, at this location of the second reflecting surface, the second reflecting surface does not prohibit the light passageway from the light source to the first reflecting surface.
In another vehicle light made in accordance with the third aspect of the invention, light rays, which directly travel from the light source to the projection lens or are reflected by the major reflecting surface, are incident to the projection lens. Such light rays are refracted in a converging manner by a predetermined degree to the forward of the vehicle light by the projection lens when passing through the projection lens. Light rays reflected by the third reflecting surface are further reflected by the fifth reflecting surface into a front downward direction of the vehicle light such that a wide area in front of the vehicle is illuminated. Herein, when the second reflecting surface is inserted in a light passageway from the light source to the first reflecting surface, light rays emitted from the light source to the first reflecting surface are not incident on the first reflecting surface, but reflected by the second reflecting surface and then by the fourth reflecting surface. Light rays reflected by the fourth reflecting surface travel to a front direction of the vehicle light, which is inclined to a predetermined side, i.e., either left or right, of the vehicle, for illuminating a road side such as a curb on the road, or a shoulder. If the fourth reflecting surface is located at the left side of the major reflecting surface while the first reflecting surface is located at the right side of the major reflecting surface, the light reflected by the fourth reflecting surface travels to the left front of the vehicle. If the fourth reflecting surface is located on the right side of the major reflecting surface while the first reflecting surface is located at the left side of the major reflecting surface, the light reflected by the fourth reflecting surface travels to the right front of the vehicle. Accordingly, when the vehicle drives on a curve or a corner to the left, the still another vehicle light located on the left side of the vehicle body can illuminate a road along a curving travelling direction, i.e., left front direction, with an increased illuminated area, while the vehicle light located on the right side of the vehicle body can illuminate the road intensively to the center front of the vehicle.
When the second reflecting surface is removed from the light passageway from the light source to the first reflecting surface, light rays emitted from the light source to the first reflecting surface are incident on the first reflecting surface. The first reflecting surface reflects such light rays to the projection lens. Such light rays are refracted in a converging manner by a predetermined degree to the forward of the vehicle when passing through the projection lens, then illuminate an area in the vicinity of a center line on the road when the vehicle travels straight ahead.
As described in the above, a portion of light distribution pattern of the vehicle light according to the third aspect of the present invention can be selectively switched by movement of the second reflecting surface between a first light distribution for illuminating forward of the vehicle by the first reflecting surface and a second light distribution for illuminating a predetermined front direction of the vehicle, which is inclined to a predetermined side, either left or right, of the vehicle light. If the fourth reflecting surface is located on the left side of the major reflecting surface while the first reflecting surface is located on the right side of the major reflecting surface, the light reflected by the fourth reflecting surface is directed to the left front of the vehicle. If the fourth reflecting surface is located on the right side of the major reflecting surface while the first reflecting surface is located on the left side of the major reflecting surface, the light reflected by the fourth reflecting surface is inclined to the right front of the vehicle. In the structure described in the above, it is sufficient to move only the second reflecting surface in order to change an illuminated area, i.e., light distribution characteristics, of the vehicle light. In order to change the location of the second reflecting surface, a relatively small space is sufficient for the movement of the second reflecting surface. Further, when the second reflecting surface is removed from the light passageway from the light source to the first reflecting surface, the second reflecting surface can be located in a shadow region of the third reflecting surface, i.e., a back surface of the third reflecting surface in a viewpoint from the light source. Accordingly, at this location of the second reflecting surface, the second reflecting surface does not prohibit the light passageway from the light source to the first reflecting surface.
In a fourth aspect of the invention, a vehicle light can include a light source, a major reflecting surface for reflecting light rays from the light source to the forward, a projection lens for refracting light rays from the major reflecting surface and directly from the light source in a converging manner to the forward by a predetermined degree, a shutter located in a light passageway from the light source to the projection lens for prohibiting an unnecessary portion of image of light rays in the vicinity of the focus of the projection lens on formation of a light distribution pattern, with the following characteristics. The shutter preferably includes a fixed portion and a movable portion capable of laterally moving to be inserted in or removed from the light passageway. A portion of the movable portion overlaps with the fixed portion. By movement of the movable portion of the shutter, a shape of a cut-off portion of the light distribution pattern can be varied.
On formation of a low beam mode light distribution pattern of the vehicle light having a cut-off line comprising an inclined cut-off line element and at least two horizontal cut-off line elements connected to each end of the inclined line element, when the movable portion of the shutter is located at its fully inserted position, the fixed portion of the shutter forms an upper horizontal cut-off line element located at a predetermined side of a vertical axis on a screen, the movable portion of the shutter forms the inclined cut-off line element which inclines from an inner end of the upper horizontal cut-off line element, which end is closer to the center of the light distribution pattern than another end of the upper horizontal cut-off line element, into a downward direction toward the vertical axis. The movable portion of the shutter also forms a lower horizontal cut-off line element connected to the lower end of the inclined cut-off line element.
At least the movable portion of the shutter is preferably concave when viewed in a direction facing to the projection lens. The movable portion of the shutter is movable, preferably in a rotating manner, around a vertical axis located at the side of the projection lens.
It is preferable that the movable portion of the shutter can be moved between its fully inserted position and its removed position relative to the light passageway, depending on a steering angle.
A driving mechanism that moves the movable portion of the shutter preferably includes a return spring to pull the movable portion of the shutter to its fully inserted position, and a stopper retaining the movable portion of the shutter in the fully inserted position.
A vehicle light according to a fifth aspect of the invention can include a light source, a major reflecting surface for directing light rays emitted from the light source to the forward of the vehicle light which is substantially parallel to an optical axis of the vehicle light, a projection lens for converging light rays incident thereto by a predetermined degree, a shutter located in a light passageway from the light source to the projection lens for prohibiting a portion of light rays which is unnecessary for formation of a light distribution pattern, and following three reflecting surfaces, i.e., first, second, fourth reflecting surfaces. A first reflecting surface reflects a portion of light rays emitted from the light source to be incident into the projection lens. A second reflecting surface is disposed to be capable of being inserted in, or removed from, a light passageway from the light source to the first reflecting surface. When the second reflecting surface is located in its fully inserted position relative to the light passageway from the light source to the first reflecting surface, a portion of light rays emitted from the light source to the second reflecting surface are reflected to the fourth reflecting surface, and the fourth reflecting surface reflects the light rays to illuminate a rather wide downward area in front of the vehicle, while the other portion of light rays emitted from the light source are reflected by the third reflecting surface to a fifth reflecting surface or incident to the projection lens. The fifth reflecting surface reflects the light rays to the front of the vehicle light to illuminate a wide area in front of the vehicle. The light rays incident to the projection lens are refracted in a converging manner to the forward of the vehicle light by a predetermined degree to illuminate the vicinity of the center of the light distribution pattern including an elbow portion. When the second reflecting surface is removed at least partly from the light passageway from the light source to the first reflecting surface, at least a portion of light rays are incident to the first reflecting surface, and reflected thereby to the projection lens. Light rays incident from the first reflecting surface to the projection lens forms a variable element of the light distribution pattern.
The shutter preferably includes a fixed portion, a movable portion capable of lateral movement from its inserted portion in a corresponding light passageway, e.g. a light passageway from the light source to the first reflecting surface, and a driving mechanism for moving the movable portion. At least a portion of the movable portion overlaps with the fixed portion. The movable portion can be moved relative to the fixed portion of the shutter in accordance with operation of the driving mechanism. Corresponding to operation of the driving mechanism, the second reflecting surface is removed from the light passageway from the light source to the first reflecting surface by a predetermined degree such that shape of a cut-off portion of the light distribution pattern is varied.
According to the fourth aspect of the invention, light rays directly come from the light source, and those reflected by the major reflecting surface are incident to the projection lens. When those light rays pass through the projection lens, the light rays are refracted in a converging manner to the forward of the projection lens by a predetermined degree such that a predetermined area on the road is illuminated. Before incident to the projection lens, a portion of light rays which is unnecessary for formation of the light distribution pattern is prohibited (blocked) by the shutter. By a shutter configuration according to the fourth aspect of the invention, the light distribution pattern can have an illuminated area with a longer distance at the side of an on-coming lane in comparison with a conventional vehicle light without glaring a driver of a car running on the on-coming lane, when the vehicle drives on a curve or turns around a corner.
More specifically, the movable portion of the shutter is laterally moved relative to the fixed portion of the shutter such that shape of a cut-off portion of the light distribution pattern is varied in a vertical direction on a screen, thereby an illuminated distance of the light distribution pattern at the side of the on-coming lane is increased to provide sufficient visibility at the side of the on-coming lane.
According to the fourth and fifth aspects of the invention, by lateral movement of the movable portion of the shutter, shape of a cut-off portion of the light distribution pattern can be varied. Therefore, for example, when the vehicle drives on a curve or a corner to the right, an illuminated distance of the light distribution pattern at the side of the on-coming lane can be increased such that visibility to the forward of traveling direction of the corner or the curve, i.e., a right front direction of the vehicle, is improved. In addition, since the movable portion of the shutter moves laterally, vertical movement of a cut-off line is limited to a predetermined range. Therefore, it is able to precisely adjust and determine the cut-off line of the light distribution pattern.
In this shutter structure, when the movable portion of the shutter is fully inserted in the light passageway from the light source to the projection lens, the fixed portion forms an upper horizontal cut-off line element located at a predetermined side of the vertical axis on the screen, and that the movable portion forms an inclined cut-off line element which inclines from an inner end of the upper horizontal cut-off line element in a downward direction to the other side of the predetermined side of the vertical axis, and that the movable portion also forms a lower horizontal cut-off line element connected to the lower end of the inclined cut-off line element, light distribution pattern of light that has passed through the projection lens varies as follows. When the movable portion of the shutter is fully inserted in the light passageway, the movable portion of the shutter forms an inclined cut-off line element extending from the vicinity of the center of the light distribution pattern in an upward direction to the predetermined side, and a lower horizontal cut-off line element connected to a lower end of the inclined cut-off line element such that a cut-off portion of the light distribution pattern is located mainly at the side of the on-coming lane, thereby the light distribution pattern has a relatively short illuminated distance at the side of the on-coming lane.
On the other hand, when the movable portion of the shutter is laterally moved from its fully inserted position toward the other side of an on-coming lane side such that the movable portion of the shutter is located between the fully inserted position and the removed position relative to the light passageway, a portion of an inclined cut-off line element located in the vicinity of the center of the light distribution pattern when the second reflecting surface is located in its fully inserted position is laterally moved toward the side of an on-coming lane, while a portion of a lower horizontal cut-off line element corresponding to the removed distance of the movable portion of the shutter is moved to the upward such that a middle horizontal cut-off line element appears between the lower and upper horizontal cut-off line elements. The middle horizontal cut-off line element is formed by a portion of an upper edge element of the fixed portion of the shutter. An upper edge of the fixed portion of the shutter comprises an upper horizontal edge element, a lower horizontal edge element, and an inclined edge element connecting between the upper and lower edge elements. The upper edge of the fixed portion of the shutter forms a cut-off line when the shutter is removed from the light passageway from the light source to the projection lens.
Accordingly, at a predetermined side of the vertical axis on the screen, i.e., an area from the center to the side of the same lane, glare light directed at another vehicle traveling ahead of the vehicle is prevented by a corresponding cut-off portion of the light distribution pattern which is an upper area of a corresponding portion of the cut-off line constituted by an upper horizontal cut-off line element formed by the lower horizontal upper edge element of the fixed portion of the shutter, an inclined cut-off line element formed by the inclined upper edge element of the fixed portion of the shutter, and a middle horizontal cut-off line element formed by an upper horizontal upper edge element of the fixed portion of the shutter. On the other hand, at the other side of the predetermined side of the vertical axis on the screen, i.e., an area from the center to the side of the on-coming lane, a cut-off line element can be varied to increase an illuminated distance to the front of the vehicle in a range that glare light to at least another driver of the vehicle traveling ahead of the vehicle on the same lane can be prevented. Depending on the range of increase of the illuminated area, glare light to drivers of vehicles traveling both ahead of the vehicle and on the on-coming lane can be prevented. Therefore, when the vehicle drives on a curve or a corner whose curving direction is toward an on-coming lane, the vehicle light can provide a sufficiently bright field of vision by increasing an illuminated distance at the side of the on-coming lane, thereby visibility to the forward of the curve or the corner is improved without glare directed at a driver of another car running ahead of the vehicle.
In the structure in which at least the movable portion of the shutter is concave when viewed in a direction facing to the projection lens and is disposed to be movable, preferably in a rotating manner, around a vertical axis located at the side of the projection lens, since the movable portion of the shutter can be laterally moved from its fully inserted position to its removed position relative to the light passageway from the light source to the projection lens, the movement of the movable portion of the shutter can be adjusted with high precision. This structure decreases the cost associated with complicated or large sized driving mechanisms of the movable portion of the shutter.
In case that the movable portion of the shutter can be moved from its fully inserted position to its removed position depending on a steering angle, as the steering angle increases, the movable portion of the shutter laterally moves at a larger rotating angle. At this time, if a vehicle light is designed to drive normally in a left lane, in an area from the center to the left side of the vertical axis on the screen, the fixed portion of the shutter forms an upper horizontal cut-off line element and an inclined cut-off line element, and the movable portion of the shutter forms a middle horizontal cut-off line element in order to prevent from providing glare light to a driver of a car running ahead of the vehicle. In an area from the center to the right side of the vertical axis on the screen, i.e., on the side of an on-coming lane, the cut-off line varies at a wide horizontal angle range relative to a crossed point of the vertical and horizontal axes on the screen, i.e., a light source position on the screen, such that an illuminated distance to the front at the on-coming lane side of the vehicle is increased. It is preferable that, as radius of curvature of the curve is smaller, the horizontal angle range of the illuminated area by the vehicle light increases at the side of on-coming lane such that visibility to the forward of the curve or corner is improved.
In the fourth and fifth aspects of the present invention, the driving mechanism of the shutter can include a return spring for pulling the movable portion of the shutter to its fully inserted position relative to a corresponding light passageway, and a stopper for retaining the movable shutter in the fully inserted position. When the driving mechanism is not operated, the movable portion of the shutter is located in its fully inserted position. Accordingly, even when the driving mechanism malfunctions, the movable portion of the shutter is pulled to and retained in the fully inserted position. Therefore, the vehicle light comprising this driving mechanism of the shutter does not inadvertently provide an excessively long illuminated distance at the side of the on-coming lane.
According to the fifth aspect of the invention, light rays which directly emanate from the light source or are reflected by the major reflecting surface are incident to the projection lens. When the light rays pass through the projection lens, the light rays are refracted in a converging manner to the forward of the projection lens by a predetermined degree.
When the second reflecting surface is fully inserted in a light passageway from the light source to the first reflecting surface, light rays emitted from the light source to the second reflecting surface are reflected by the second reflecting surface and further by the fourth reflecting surface. The fourth reflecting surface reflects the light rays to the forward of the vehicle to illuminate a rather wide downward area in front of the vehicle light. Accordingly, when the vehicle drives on a straight way, the vehicle light can illuminate a traveling direction of the road, i.e., straight forward, with an increased amount of light.
When the second reflecting surface is located away from the light passageway from the light source to the first reflecting surface, light rays emitted from the light source to the first reflecting surface are reflected by the first reflecting surface to be incident to the projection lens. The light rays pass through the projection lens, and travel forward to intensively illuminate an increased illuminated area formed by removal of the movable portion of the shutter from its corresponding light passageway. The increased illuminated area is preferably an approximate band located slightly under the horizontal axis on the screen, which band variably extends from the center to the on-coming lane side of the vertical axis on the screen.
Corresponding to the movement of the second reflecting surface from its fully inserted position relative to the light passageway from the light source to the first reflecting surface, the movable portion of the shutter is laterally moved from its fully inserted position to its removed position relative to the light passageway from the light source to the projection lens, thereby a shape of a cut-off portion of the light distribution pattern is varied such that a portion of a cut-off line varies in a vertical direction while a sufficient amount of light is provided along a curving traveling direction of the vehicle, when the vehicle drives on a curve or turns around a corner.
By movement of the movable portion of the shutter, a cut-off portion of the light distribution pattern is varied such that an illuminated area at the side of the on-coming lane is increased. Further, by movement of the second reflecting surface corresponding to an operation of a driving mechanism for moving the second reflecting surface, an amount of light illuminated to the side of an on-coming lane is increased. Accordingly, by simultaneous movement of the movable portion of the shutter and the second reflecting surface, when the vehicle drives on a curve or turns around a corner whose curving direction is toward the on-coming lane, e.g., to the right in a case that the vehicle is required to drive normally on a left lane on a road, an illuminated distance at the side of the on-coming lane is increased, and sufficient visibility to the side of the on-coming lane, i.e., the forward of the curve, can be obtained.
In the fifth aspect of the invention, by movement of the second reflecting surface, a traveling direction of a portion of light rays emitted from the light rays are selectively and gradually switched between a rather wide downward area of the light distribution pattern via the second and fourth reflecting surfaces, and the variable portion which is a predetermined area of the light distribution pattern from the center to the side of on-coming lane. The movable portion of the shutter moves in line with the second reflecting surface such that an illuminated distance at the side of the on-coming lane is increased. In the fifth aspect of the invention, it is sufficient to move only the second reflecting surface and the movable portion of the shutter for switching the illuminated area on the road, i.e., light distribution characteristics. Accordingly, a required space for movement of the second reflecting surface and the movable portion of the shutter is relatively small.
In a sixth aspect of the invention, a vehicle light can include a light source, a major reflecting surface directing light emitted from the light source to the forward of the vehicle light, a projection lens for refracting light from the light source and the major reflecting surface in a converging manner by a predetermined degree, a shutter located in the light passageway from the light source to the projection lens for prohibiting an unnecessary portion of light on formation of a light distribution pattern, and following three reflecting surfaces. A first reflecting surface is an ellipse group reflecting surface having a focus in the vicinity of the light source. The first reflecting surface can move around the longitudinal axis of the ellipse group first reflecting surface in a rotating manner to be inserted in or removed from the light passageway from the light source to a third reflecting surface. A second reflecting surface comprises at least one parabolic group reflecting surface element having a focus in the vicinity of the second focus of the first reflecting surface. The second reflecting surface is concave when viewed in a direction facing to the front of the vehicle light. The third reflecting surface comprises at least one elliptic group reflecting surface element which reflects light rays from the light source to the forward of the vehicle light when the first reflecting surface is at least partly removed from the light passageway from the light source to the third reflecting surface. Light rays from the third reflecting surface are converged by a predetermined degree when passing through the projection lens, and illuminate the forward of the vehicle light.
When the vehicle drives on a curve, e.g., a curve to the left, the first reflecting surface is moved in a predetermined direction, i.e., to the right, to be located in a predetermined position such that at least a portion of light rays becomes incident on a predetermined portion of the third reflecting surface, while the other portion of light rays are reflected by the first reflecting surface to be incident on a predetermined portion of the second reflecting surface.
The first reflecting surface can be divided into at least two first reflecting surface elements, each element can be separately moved to be inserted in or removed from the light passageway from the light source to the third reflecting surface. When the vehicle travels on a curve, e.g., a curve to the left, one predetermined first reflecting surface element, e.g., a right one relative to the optical axis X of the vehicle light, can solely move in one predetermined direction, e.g., to the right, to pass through at least a portion of light rays from the light source to the third reflecting surface, while another predetermined first reflecting surface element is fixedly located to reflect light rays from the light source to the second reflecting surface.
It is preferable that the first reflecting surface or the first reflecting surface elements can be moved from their respective inserted positions to removed positions depending on steering angle detected or road condition information obtained through a car navigation system.
The vehicle light according to the sixth aspect further preferably includes a sixth reflecting surface located inside of the first reflecting surface. The sixth reflecting surface is preferably an ellipse group reflecting surface having a first focus in the vicinity of the light source, and can include a center aperture and at least one aperture located in the vicinity of an upper edge of the sixth reflecting surface. The aperture located in the vicinity of an upper edge of the sixth reflecting surface can be a window portion.
The vehicle light according to the sixth aspect further preferably includes a plurality of projection lenses, each projection lens corresponding to each passageway of light reflected by a corresponding portion of the third reflecting surface to the forward.
In the sixth aspect of the invention, the shutter has a similar structure to that of the fourth and fifth aspects, including a fixed portion and a movable portion located to at least partly cover the fixed portion. The movable portion can be laterally moved from its inserted position relative to a light passageway from the light source to the projection lens, while the fixed portion is fixedly located. A shape of a cut-off line of the light distribution pattern can be varied by movement of the movable portion of the shutter.
In the sixth aspect of the invention, the vehicle light preferably further includes a plurality of shutters corresponding to each passageway of light reflected by a corresponding portion of the third reflecting surface to the forward.
In the sixth aspect of the present invention, the vehicle light preferably further includes at least one fourth reflecting surface located at at least one predetermined outer side, i.e., either right outside or left outside, of the second reflecting surface, and at least one fifth reflecting surface located on at least one predetermined outer side of the third reflecting surface, when viewed laterally, which side is the other side of the predetermined side on which the fourth reflecting surface is located, i.e., either left or right. At this time, the aperture in the vicinity of the upper edge of the sixth reflecting surface, if any, and the first reflecting surface or the first reflecting surface element respectively have appropriate sizes to cover corresponding light passageways from the light source to corresponding portions of the third reflecting surface and the fifth third reflecting surface. The fourth reflecting surface can be a continuous smooth surface, or a separate surface, from the second reflecting surface. The fifth reflecting surface can be a continuous smooth surface, or a separate surface, from the third reflecting surface.
The fourth reflecting surface reflects light rays from a corresponding portion of the first reflecting surface to a forward direction which is inclined to a predetermined side, i.e., either left or right, of the vehicle light. The fifth reflecting surface reflects light rays from the light source to the central forward in a converging manner by a predetermined degree, when the first reflecting surface or the first reflecting surface element is removed at least partly from the light passageway from the light source to the fifth reflecting surface.
In the sixth aspect of the invention, when the vehicle drives at a high speed, the first reflecting surface or all of the first reflecting surface elements is preferably fully removed from the light passageway from the light source to all of the third and fifth reflecting surface elements.
In the sixth aspect of the invention, light rays emitted from the light source directly to the projection lens, and light rays reflected by the major reflecting surface are incident to the projection lens. Light rays incident to the projection lens are refracted by a predetermined degree to the front focus of the projection lens when passing through the projection lens, and further travel to the forward to illuminate a predetermined area on a road. A portion of light rays incident to the projection lens are prohibited or cut-off by the shutter such that the light distribution pattern has a relatively shorter illuminated distance at the side of the on-coming lane. Further, when the first reflecting surface is located in the light passageway from the light source to the third reflecting surface, light rays incident on the first reflecting surface are reflected thereby to the second reflecting surface. The second reflecting surface reflects light rays to a front downward direction in a converging manner by a predetermined degree to illuminate a predetermined area on the road. Herein, when the first reflecting surface or a predetermined first reflecting surface element starts to remove from its fully inserted position relative to the light passageway, a portion of light rays traveling from the light source to the vicinity of the fully inserted position of the first reflecting surface or the first reflecting surface element, pass through the removed area of the first reflecting surface or the first reflecting surface element, and reach a corresponding portion of the third reflecting surface. The third reflecting surface reflects such light rays to illuminate a predetermined front area under a horizontal axis on a screen with a sufficient light amount to the downward. A general traveling direction of light rays reflected by the third reflecting surface and which have passed through the projection lens is slightly inclined to a predetermined side, either right or left, relative to the optical axis of the vehicle light, which side is a traveling direction of the vehicle. Accordingly, when the vehicle drives on a curve, an illuminated distance into the traveling direction of the vehicle is increased, and visibility to the forward in the traveling direction of the vehicle is improved.
Further, when the first reflecting surface or all of the first reflecting surface elements are fully removed from the light passageway from the light source to the third reflecting surface depending on a traveling direction of the vehicle, e.g., the vehicle travels straight ahead at a high speed, all of the light rays directing from the light source to the inserted position(s) of the first reflecting surface or the first reflecting surface elements, pass through an aperture(s) formed by removal of the first reflecting surface or the first reflecting surface elements corresponding to the fully inserted position(s), and travel to the third reflecting surface. The third reflecting surface reflects such light rays to illuminate a predetermined front area under a horizontal axis on a screen with sufficient light amount to the downward direction. A general traveling direction of light rays reflected by the third reflecting surface that passes through the projection lens is slightly inclined to the traveling direction of the vehicle relative to the optical axis of the vehicle light, e.g., a straight forward direction substantially parallel to the optical axis of the vehicle light. Accordingly, illuminance to the traveling direction of the vehicle is improved, and visibility to the traveling direction of the vehicle is improved.
When the vehicle travels on a curve, e.g., a curve to the left, the first reflecting surface or a predetermined first reflecting surface element located at a predetermined side, e.g., the right, relative to the optical axis of the vehicle light solely moves in a direction opposite to the curving direction, e.g., to the right, in a rotating manner. Light rays that have passed through an aperture formed at one side, e.g., right, of the optical axis of the vehicle light by removal of the first reflecting surface or the corresponding first reflecting surface element become light rays traveling to the another side, e.g., left, after being reflected by a corresponding portion of the third reflecting surface and passing through the corresponding projection lens, if any. More specifically, after being reflected by the corresponding portion of the third reflecting surface, and passing through the projection lens, if any, the light rays illuminate a front downward area slightly under a horizontal axis on the screen. A general traveling direction of light rays reflected by the corresponding portion of the third reflecting surface, and passing through the projection lens, if any, is slightly inclined to the traveling direction of the vehicle relative to the optical axis of the vehicle light, e.g., left forward direction. Accordingly, when the vehicle travels on a curve, e.g., a curve to the left, an illuminated distance to the front of the vehicle light which is inclined to a predetermined side, e.g., left, is increased such that visibility to the front of the vehicle at the side of lateral traveling direction, e.g., a left front of the vehicle, is improved.
In case that the first reflecting surface is moved in a rotating manner from its fully inserted position to its removed position relative to the light passageway from the light source to the third reflecting surface based on a detected steering angle and/or information on road conditions obtained by a car navigation system, the first reflecting surface or the first reflecting surface element can be gradually moved in a lateral direction from its fully inserted position. Thereby, a horizontal angle range relative to the light source position of an illuminated area illuminated by the light rays which passed through an aperture formed by removal of the first reflecting surface or the corresponding first reflecting surface element and reflected by the third reflecting surface, is increased such that an illuminated distance toward a traveling direction of the vehicle, which is inclined to either left or right relative to a vertical axis on the screen, is increased. As radius of curvature of the curve is smaller, the horizontal angle range of the illuminated area and the illuminated distance into a predetermined side front of the vehicle are set to be larger. Accordingly, the vehicle light can provide superior visibility to the forward of the curve.
If the sixth reflecting surface is located inside the first reflecting surface, or inside both the first and fourth reflecting surfaces, the sixth reflecting surface is an ellipse group reflecting surface having a focus in the vicinity of the light source, and comprising a center aperture located in the vicinity of the light passageway from the light source directly to the projection lens, and at least one aperture located in the vicinity of the upper edge of the sixth reflecting surface. If only one aperture is included around the upper edge, a center line of a width of the aperture is located along the optical axis direction of the vehicle light, and substantially symmetrical relative to the center line. If an even number of apertures is included, a center line, which passes through a center of a width of a sixth reflecting surface portion located between the two central apertures, is located along the optical axis direction of the vehicle light, and substantially symmetrical relative to the center line.
Light rays emitted from the light source to the direct front, and light rays reflected by the major reflecting surface are incident to the projection lens. When passing through the projection lens, the light rays are refracted by a predetermined degree in a converging manner to a front focus of the projection lens, and illuminate a predetermined area on the road.
When the first reflecting surface or the first reflecting surface element(s) is(are) located in its fully inserted position(s), light rays incident to the aperture(s) of the sixth reflecting surface are reflected by the first reflecting surface or the corresponding first reflecting surface element(s), and further reflected by the second reflecting surface or the corresponding second reflecting surface element(s). When the light rays are reflected by the second reflecting surface or the corresponding second reflecting surface element(s), the light rays are converged by a predetermined degree and illuminate a predetermined area on the road, i.e., front downward.
When the first reflecting surface or the first reflecting surface element(s) start to move from its (their) fully inserted position(s) in a direction away from the light passageway, at least a portion of light rays directing from the light source to the third reflecting surface or third reflecting surface element(s) pass through the aperture or corresponding aperture(s) of the sixth reflecting surface without being reflected by the first reflecting surface or the corresponding reflecting surface element(s). The third reflecting surface or the corresponding third reflecting surface element(s) reflects light rays to the forward of the vehicle to illuminate a predetermined area slightly under the horizontal axis on the screen. A general direction of light rays reflected by the third reflecting surface or the third reflecting surface element(s) is slightly inclined to a predetermined side relative to the optical axis of the vehicle light, which side is in the traveling direction of the vehicle.
If a plurality of projection lenses are arranged for each light passageway from each third reflecting surface element, light rays from the third reflecting surface are converged in a unit of every light passageway to each projection lens respectively by an appropriate degree for illuminating a respective predetermined area on the road with predetermined light distribution characteristics.
If the shutter includes a fixed portion which is fixedly located, and a movable portion which overlaps at least partly with the fixed portion and is capable of lateral movement from its fully inserted position relative to the light passageway from either the light source or a corresponding portion of the third reflecting surface element to the corresponding projection lens, a shape of a cut-off line of the light distribution pattern can be varied by lateral movement of the movable portion relative to the fixed portion of the shutter such that location of a portion of the cut-off line is varied in a vertical direction. Thereby, when the vehicle drives on a curve or turns around a corner, an illuminated distance into a traveling direction of the vehicle can be increased to provide sufficiently improved visibility to the forward of the curve or the corner.
In the case when a plurality of shutters are arranged for each light passageway from the third reflecting surface element to the forward, all the shutters can be fixedly located and do not include any movable portion, or alternatively, all the shutters can respectively include a movable portion. If all the shutters can respectively include a movable portion, all the shutters have substantially the same structure among them except their sizes. If all the shutters do not have any movable portion, the shutter located in the light passageway along the optical axis of the vehicle light provides a fixed element of the light distribution pattern at any time of operation of the vehicle light. By movement of the first reflecting surface or the corresponding first reflecting surface element(s), light rays become incident to either the third reflecting surface or the corresponding third reflecting surface element(s), and the corresponding projection lens(s). As a result, if all the shutters respectively have a movable portion, a shape of a cut-off line of the light distribution pattern is varied in a vertical direction to increase an illuminated distance to the traveling direction when driving on the curve or turning around a corner such that visibility to the forward of a curve or corner is improved. The shutters located in the respective light passageways from the corresponding portion of the third reflecting surface are preferably designed such that light rays that have passed through the corresponding projection lens illuminate an increased illuminated area of the light distribution pattern in accordance with the movement of the first reflecting surface or the corresponding first reflecting surface element(s). If all the shutters have no movable portion, an entire shape of the light distribution pattern may not be varied, but light intensity illuminating forward of the curve or corner is increased such that visibility to the forward of the curve or corner is improved. Since no movable portion is included in the shutter, a structure of the vehicle light assembly can be simplified, which leads to cost reduction and easy maintenance.
In the case that the vehicle light according to the sixth aspect of the invention further includes at least one fourth reflecting surface located at at least one predetermined outer side, e.g., left side, of the second reflecting surface, and at least one fifth reflecting surface located at at least one predetermined outer side, e.g., right side, of the third reflecting surface, when the first reflecting surface or the first reflecting surface element(s) is partly inserted in the light passageway from the light source to the fifth reflecting surface, light rays reflected by the first reflecting surface and fourth reflecting surfaces illuminate a predetermined side front area, e.g. a front left side area, thereby sufficient field of vision to the predetermined side front is obtained. On the other hand, light rays that have passed through an aperture formed by removal of the first reflecting surface or the first reflecting surface element are reflected by the fifth reflecting surface, and illuminate a predetermined front area located slightly under the horizontal axis on the screen such that an illuminated distance to the front at the side of a traveling direction of the vehicle, when viewed laterally, e.g., a front area at the right side of the vertical axis on the screen, is increased to improve visibility to the traveling direction of the vehicle.
When the vehicle travels at a high speed, it is preferable that the first reflecting surface or all the first reflecting surface elements be completely removed from the light passageway(s) from the light source to the fifth reflecting surface. Illumination to the side front is not required when the vehicle travels at high speed. Therefore, it is preferable to switch light distribution from the side front to the direct front area under the horizontal axis on the screen to increase an illuminated distance to the direct front area such that visibility to the front of the vehicle is improved when the vehicle travels at a high speed.
Additional features, advantages, and embodiments of the invention may be set forth or apparent from consideration of the following detailed description, drawings, and claims. Moreover, it is to be understood that both the foregoing summary of the invention and the following detailed description are exemplary and intended to provide further explanation without limiting the scope of the invention as claimed.